1. Field of the Invention
The invention is directed to a ceiling board and, more particularly, to a perforated ceiling board with a vinyl facing.
2. Description of the Prior Art
Typical of the standard fiber composition ceiling boards is that shown in U.S. Pat. No. 2,791,289, which issued to D. A. Proudfoot et al. This patent shows a fiberboard ceiling product which has been provided with perforations 11 due to the use of pin punches 12. These ceiling boards are made from either vegetable fiber or mineral wool fiber, and are laid up in mat form by several different techniques.
U.S. Pat. No. 3,437,551 discloses a polyurethane panel which has a thermoplastic film adhered thereto. This patent teaches that a plug of material must be removed from a laminate structure of vinyl and foam or else the foam would close up any perforation which is made by a punch which merely pierced the foam. With vegetable fiber and mineral wool fiberboards, there is usually no condition involving the closing up of a perforation made by a punch such as you would encounter with a foam material.
The invention herein is in the utilization of a base of a conventional fiber material which holds its shape once it is perforated, but providing an overlaying structure of a plasticized material which will tend to grow and form a smaller hole after a punch has been withdrawn from the composite structure. Consequently, a unique design effect is formed without any loss of sound-absorbing qualities.